Mesozoic volcanic activity and uranium mineralization of Duolun volcanic basin in the west of Yanshan-Liaoning uranium-metallogenetic belt

Duolun basin, located in the west of Yanshan-Liaoning uranium-metallogenetic belt, is a volcanic eruption basin and contains nine calderas which include Zhenzi and Xigangou caldera et al. More than twenty volcanic type uranium anomaly and mineralization spots have been found in the calderas of the Southern Duolun basin, suggesting close connection with volcanic activities. Uranium mineralization is typically occurred in volcanic structures and ore-bearing formations are sub-volcanic rocks and acid volcanic rocks. Subaerial clayization and deep subsurface silicification, hematization, fluoritization and metal sulfide assemblages imply the occurrence of moderate-to-low temperature hydrothermal fluids with volcanic activities. Drilling exploration verified that uranium mineralization occurred in inner and outer contact zone of sub-volcanic plutons in fish-bone shape. Research on the relationship between volcanic activity and uranium mineralization indicates that Duolun basin is potential for volcanic-type uranium deposits. (authors)